from rest_framework.views import exception_handler as drf_exception_handler
from django.db import DatabaseError
from redis.exceptions import RedisError
from rest_framework.response import Response
from rest_framework import status

import logging

# 获取在配置文件中定义的logger日志处理对象，用来记录日志
logger = logging.getLogger('django')

def exception_handler(exc, context):
    """
    自定义异常处理
    :param exc: 异常对象
    :param context: 抛出异常的上下文[异常相关信息]
    :return: Response响应对象
    """
    # 调用drf框架原生的异常处理方法
    response = drf_exception_handler(exc, context)

    # 判断当前本次异常是否是drf所无法识别
    if response is None:
        # 获取异常发生时的视图对象
        view = context['view']
        # 判断是否数据库或redis异常
        if isinstance(exc, DatabaseError) or isinstance(exc, RedisError):
            # 记录错误信息到日志中
            logger.error('[%s] %s' % (view, exc))
            # 返回异常信息给客户端
            response = Response({'message': '服务器内部错误'}, status=status.HTTP_507_INSUFFICIENT_STORAGE)

    return response